If you mean single Roman letters, they can either stand for numbers or abbreviations.If you mean single Roman letters, they can either stand for numbers or abbreviations.If you mean single Roman letters, they can either stand for numbers or abbreviations.If you mean single Roman letters, they can either stand for numbers or abbreviations.If you mean single Roman letters, they can either stand for numbers or abbreviations.If you mean single Roman letters, they can either stand for numbers or abbreviations.If you mean single Roman letters, they can either stand for numbers or abbreviations.If you mean single Roman letters, they can either stand for numbers or abbreviations.If you mean single Roman letters, they can either stand for numbers or abbreviations.
444
519
269
48
464
224
2
19
999
1776
8